Ecology is a branch of science that deals with the inter-relationship between biotic (living) and abiotic (non-living) components of nature as well as with the relationship among the individuals, population and community of the biotic components.
The term 'ecology' is derived from two Greek words oinks (meaning house) and logos (meaning study of) and is used to denote the relationship between the organisms and their environment.
Ecology has been defined in a number of ways. According to Woodbury (1954), 'Ecology is a science which investigates organisms in relation to their environment'. E.P. Odom (1969) defined ecology as 'the study of structure and function of nature'. The most acceptable definition of ecology was proposed by Charles Krebs (1985), Ecology is the scientific study of the interaction that determines the distribution and abundance of organisms.
In ecology, the term 'habitat' is used to denote the place where an organism's or species' population lives, for example pond. A pond is the habitat of zooplankton and fish. 'Niche' is the fundamental unit of an organism's or species' population in the community.
Whereas 'habitat' is the place where an organism lives, 'niche' is the activity (functional) aspect of the organism. 'Population' is used to denote groups of individuals of any one kind of organism and 'community' or biotic community includes all the populations of a given area, called habitat.
Ecology plays a significant role in our day-to-day life. It is concerned with agriculture, horticulture, conservation of soil, forest, wildlife, water resources, etc.